Final answer:
Long periods of low response with sudden bursts are characteristic of the variable-interval reinforcement schedule, which provides reinforcements at unpredictable times leading to a moderate, steady rate of response.
Step-by-step explanation:
Long periods of little responding followed by a burst of responding is most characteristic of the variable-interval reinforcement schedule. This schedule provides reinforcement based on varying and unpredictable amounts of time. Unlike the fixed-interval schedule which provides reinforcement after a set amount of time and often leads to a 'scallop-shaped' response pattern as the subject increases their response rate as the time for reinforcement approaches, the variable-interval schedule yields a moderate and steady response pace as the reinforcements are given at random times. An example of this would be employees of a restaurant who are constantly motivated to perform well because they are unaware of when the quality control inspector might award a bonus.
With the variable-interval schedule, the pattern of behavior is characterized by a steadier rate of responses with no predictable peaking as seen in fixed-interval schedules. This schedule tends to produce a high level of consistency in behavior because the reinforcement is unpredictable, avoiding a drop in response rate directly after reinforcement that is seen with fixed schedules.